Table of Contents
Software-defined wide-area networking, or SD-WAN, is a flexible, enabling solution that involves the transmission of data packets across a logical overlay that leverages several existing WAN pathways based on predetermined factors and network conditions. SD-WAN is the application of the principles of software-defined networking (SDN) to wide area networks (WAN). Traditionally, connecting to a WAN was handled via a single service provider such as AT&T, Sprint, Verizon, Comcast or any carrier that can deliver long-distance connectivity options such as Multiprotocol Label Switching (MPLS) networks across Internet circuits or broadband networks. One of the primary benefits of SD-WAN is the ability to unify or bundle two or more of these pathways and virtualize them to achieve increased performance, flexibility, and resilience.
Voice and video conferencing applications are compelling use cases at the edge—both produce large amounts of, real-time data that is significantly bandwidth taxing. SD-WAN solutions can optimize data delivery by analyzing current traffic and by testing network conditions to determine the best route for the data packets. Traffic is then sent according to policies that take into account the predetermined priority of the application, the available bandwidth, and the nature of other traffic present on the unified WAN network.
To enable this responsive behavior, many SD-WAN vendors maintain configuration databases for thousands of applications and their typical network priorities, and establish default baseline information that can be used for prioritization and other characteristics. Voice and video conference apps are jitter and latency sensitive, for example, and would generally be considered high priority traffic, while email and social media can be ranked lower. These values can be tuned by organizations as needed, with some vendors providing more granular control than others.
Another important capability for SD-WAN use cases is zero-touch deployment, which allows an organization to ship SD-WAN equipment to a remote location, and have it plugged in by an office manager and working almost right away. In many cases an email link-click is all that is needed to establish a virtual SD-WAN, without any further involvement from IT.
SD-WAN presents three delivery models: Owned and operated by the customer, delivered via a managed service provider (MSP), or provided as a managed service via a carrier. SD-WAN can also be bundled with a next-generation firewall (NGFW). This last option allows for the convergence of SD-WAN and NGFW features and establishes secure connectivity that reaches from cloud apps to end devices. Some vendors will include these firewalls, while others have one or more partners to choose from for this functionality.
In this report, we identify five SD-WAN providers as Leaders in the sector. Cisco, CloudGenix, Fortinet, Silver Peak, and VMware. Of these, VMware leads in terms of overall capability and value, while CloudGenix shows the most promise with an innovative and aggressive strategy that makes it one of just two vendors in this report to earn our “Outperformer” designation.
Exploring this sector, we see vendors optimizing their products to address one or more of four (overlapping) approaches:
- Application focused: The top option here is Silver Peak, which is building on its deep WAN acceleration roots. Citrix and Fortinet both boast robust application configuration libraries, while Oracle SD-WAN is compelling when paired with Oracle Cloud applications.
- Geography focused: Aryaka stands out with its global presence and many remote PoPs and network access points (NAPs).
- Carrier oriented: Telecom carriers and large enterprises should consider VMWare, Fortinet, Silver Peak, and Nokia. All can provide SD-WAN to enterprises via numerous carriers, while allowing organizations to manage the infrastructure themselves.
- Security focused: Security is an area of intense activity in the SD-WAN space, and lead vendors here include Fortinet, Cisco, CloudGenix, and Forcepoint. Versa, too, is worth a look despite not being an established cybersecurity outfit.
The benefits of SD-WAN make it a crucial technology for which intelligent devices are proliferating at a rapid pace and putting significant strain on underlying WAN infrastructure. SD-WAN not only enables business continuity, it also supports digital transformation at the edge. As organizations have migrated to teleworking on a massive scale due to Covid-19, SD-WAN has proven to be a reliable technology that enables workers to stay productive regardless of their location, even while using poor fixed and mobile Internet links.